libstdc++-v3/src/future.cc

   1 // future -*- C++ -*-
   2
   3 // Copyright (C) 2009 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // Under Section 7 of GPL version 3, you are granted additional
  17 // permissions described in the GCC Runtime Library Exception, version
  18 // 3.1, as published by the Free Software Foundation.
  19
  20 // You should have received a copy of the GNU General Public License and
  21 // a copy of the GCC Runtime Library Exception along with this program;
  22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  23 // <http://www.gnu.org/licenses/>.
  24
  25 #include <future>
  26
  27 namespace
  28 {
  29   struct future_error_category : public std::error_category
  30   {
  31     virtual const char*
  32     name() const
  33     { return "future"; }
  34
  35     virtual std::string message(int __ec) const
  36     {
  37       std::string __msg;
  38       switch (std::future_errc(__ec))
  39       {
  40       case std::future_errc::broken_promise:
  41           __msg = "Broken promise";
  42           break;
  43       case std::future_errc::future_already_retrieved:
  44           __msg = "Future already retrieved";
  45           break;
  46       case std::future_errc::promise_already_satisfied:
  47           __msg = "Promise already satisfied";
  48           break;
  49       default:
  50           __msg = "Unknown error";
  51           break;
  52       }
  53       return __msg;
  54     }
  55   };
  56
  57   const future_error_category&
  58   __future_category_instance()
  59   {
  60     static const future_error_category __fec;
  61     return __fec;
  62   }
  63 }
  64
  65 namespace std
  66 {
  67   const error_category* const future_category = &__future_category_instance();
  68
  69   future_error::~future_error() throw() { }
  70
  71   const char*
  72   future_error::what() const throw() { return _M_code.message().c_str(); }
  73 }